-benjamin f



(NoMbdeL) E F. DILLON.

COMBINED BURGLARALAEM AND TELEPHONE SYSTEM. No.291,s10. I PatentedJaE.1,1884.

E EH3 V WITNESSES: T IILVENIQR:

/D D W& T T V I ATTORNEYS,

N. PETERS, Hlolo-Lflhowapher. Washingtan. o. c.

UNITED STATES PATENT FFiCEt BENJAMIN F. DILLON, or SAVANNAH, GEORGIA.

COMBINED BURGLAR-ALARM AND TELEPHONE S'YSTEM.

.SPECIFIOATIION forming part of Letters Patent No. 291,310, datedJanuary 1, 1854.

Application filed May 23, 1883.

(No model.)

To (Z5 whmn, it mtg concern:

Be it known that I, BENJAMIN F. DILLON,

. of Savannah, in the county of Ohatham and State of Georgia, haveinvented a new and useful Improvement in Combined Burglar-Alarm andTelephone System; and I do hereby declare that the following is a full,clear, and exact description of the same, reference being hadto theaccompanying drawing, forming part of this specification, in which thefigure is a diagram View of the central office connected with a singlesubscribers office.

The invention relates to an improvement in 1 burglar-alarm apparatus,and its adaptation to r 5 telephone-exchanges which employ a eparatewire to each subscriber for communications between its members, andanother wire common to a number of subscribers for ordinary I battery M.B, the circuit passes through relay R to point 1, which is normally incontact with key T, thence through line L to singlestroke bell B insubscribers premises, and 011 through the usual circuit-closing springslocated in the various doors, windows, &c., to the earth. Local batteryL B is in connection with magnet M and vibrating bell V B, its lineterminating at the back of the movable lever H on the a one side, and atthe fulcrum of armature-lever A L on the other. Upper lever, U L, iselectrically connected with J, and V, V, and K are in electricalconnection with each other.

As shown in the diagram,the main-line circuit 1s supposed to be brokenin one of the circuit breaking springs inside the protected building ofthe subscriber, and lever H is resting on J, so as to break the localcircuit L B.

Upon the completion of main-line circuit, re-

lay R will attract armature-lever A L against the lip of upper lever, UL, (which is held against insulated limiting-screw G by the tension ofspring S",) thus completing local circuit, causing vibrating bell toring and the drop D to fall, exposing the number of the subscriber,indicating in the central office that said subscriber has closed hispremises. Lever H is then shifted to K, so as to break local circuit.The operator then pushes key T against contact 2, throwing main linedirect to a suitable signal-battery, S B, which has the effect ofcausing subscribers single-stroke bell B to respond, thereby notifyinghim that his closing has been observed at the central office, and thatthe circuit is intact. Now, the key T having returned to its normalposition of rest on stop 1, should an attempt be made to ground orshort-circuit the line, bell B, which performs the double office of asignaling ap paratus and a resistance-coil, would be cut out of thecircuit, and the decreased resistance of line would cause relay R toexert a stronger magnetic efi'ect upon armature-lever AL, sufficient toovercome the tension of springs S and S, which are adjustable, andpulling upper lever, U L, against contact-stop NV would again completelocal circuit and absolutely indicate that the wire was grounded. Upperlever, U L, being pressed against \V by armature-lever A L, and W beingin connection with K, it will readily be seen that the local circuitwould be closed whether lever H was on J or K-acondition which couldexist under no other circumstances.

The application to telephone-exchanges is made in the following manner:A two-point switch, F, is placed in the telephone exchange and one, G,in the subscribers office. To the levers of both the main orsubscriber's private wire is connected, and to points 3 the wiresleading to the burglarconnections, and to 4 i the telephone-switch inthe central office or exchange is connected, while in the snbscrib ersoffice the telephoneinstrument is connected to this point. During theday these levers at both places are upon 4-. hen the subscriber desiresto leave his office at night, he notifies the exchange through the callwire of his intention to leave and desires the burglarconnection made,at the same time shifting his switch to point 3. The exchangeimmediately makes the same change, and after exchanging signals, asbefore explained, is satisfied that the system is all right.

5 glar-connections will effect a wonderful saving of wire and greatobstructions to streets of cities using these systems.

Having thus described my invention, what I claim as new is- 1. Acombined telephone system and burglar-alarm, consisting of atelephone-line. burglarconnections at the subscribers office, asubscriber stelephone,'a two-point switch con necting alternately withthe subscribers tele- 15 phone-instrument or his burglar-connections,

. and a central oflice having a telephone switchboard and local batterywith burglar-alarm circuit worked by relay, as described, and atwo-point switch connecting. the line alter- 20 nately with thetelephone switch-board and the relay of the burglar-alarm circuit,substantially' as set forth.

2. The combination, with the relay Roperated by the main battery andadapted to be influenced by the surreptitious grounding or breaking ofthe main circuit in one of the subscribers oflices, of the vibratingbell and localbattery circuit, the electrically-connected contact-pointsV \V K, the armature lever A L, forming one of the terminals of thelocal-battery circuit, the switch-lever H, forming the other terminal,and the lever U L, electrically connected to point J, and provided withspring S, and arranged, as described, to be struck and deflected by thearmature-lever A L, as and for the purpose described.

' BENJAMIN F. DILLON.

Vitnessos:

JAMES R.- Sn EPPARD, VVILLIAM F. KENNEDY.

